Blumax, that looks like one of my old generic B-24 skins, so it's naturally going to need some changes!
The lack of outline on the US insignia is interesting and dates the photo sometime after July '43 (when the bars first appeared) and probably before September '43 (when the red outline was replaced by blue). Sometimes it took a while for the ground crews to catch up with orders, so it could be later. If I had to guess on colors, I'd say it was OD Green over Neutral Gray. I'll guess the bombs (mission markers) and the RUTH-LESS name are yellow.
The radio operator's position was between the back end of the bomb bay and the waist guns, so THEO should be somewhere in that general vicinity. If you look very closely, you can just make out a slightly darker rectangle in the upper right corner of the photo which is one of the small side windows. In the bottom left corner there's a light part that looks like the upper edge of the (open) bomb-bay door. The panel lines agree with this location. We now have the exact position on the port side of the fuselage!